The present invention relates to a pressure body arrangement for a claw coupling.
The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
Claw couplings find application to transmit a torque between two shafts aligning with one another, such as between a motor shaft and a transmission shaft for example, and include two coupling elements disposed axially opposite one another, having end face surfaces facing towards one another, from which claws engaging alternately into one another project, and a pressure body arrangement disposed between the coupling elements and made of elastic material. The pressure body arrangement includes a ring element and pressure bodies projecting radially outwards from the ring element, which are each received between a claw of one coupling element and a claw of the other coupling element. During operation, the two coupling elements turn relative to one another in accordance with the torque present and the stiffness of the elastic material of the pressure body ring. Each claw of the coupling elements executes hereby a rotational movement, with a point of a side surface of a claw disposed radially further out moving on a greater circular track than a point of a side surface of a claw disposed radially further inwards and thereby covering a greater distance. This leads to each pressure body of the pressure body ring being pressed together more on the outside than on the inside, which results in an uneven pressure distribution, in which a higher edge pressure acts radially outwards. Accordingly the pressure bodies are pushed radially inwards during the operation of the claw coupling, thereby frequently causing a significant and undesired deformation of the ring element of the pressure body ring.
FIG. 4 shows, by way of example, a deformed pressure body ring 100 after having been dismantled. The pressure body ring 100 is made of elastic material and includes a ring element 101 and eight pressure bodies 102 which project radially outwards from the ring element 101, with the initially circular ring element 101 being heavily deformed.
Attempts have been made to prevent this deformation of the ring element by limiting the maximum permissible torque of a claw coupling. In this way impermissibly high forces directed inwards, acting on the pressure bodies, can be prevented so that deformation of the ring element of the pressure body ring, as shown in FIG. 4, could conceivably be counteracted. However, the maximum permissible torque is to be set very low here, which in many cases is undesired. Another approach involves replacing the ring element 101, shown in FIG. 4, by a circular washer, in order to lend a greater stiffness to the arrangement in the radial direction. A drawback of this approach of configuration of the pressure body arrangement resides in the fact that a shaft can then no longer project into the claw coupling, thereby restricting construction.
It would therefore be desirable and advantageous to provide an improved pressure body arrangement to obviate prior art shortcomings.